Norway’s $1 trillion sovereign wealth fund is planning to shed some of its oil investments. While the move has been celebrated as a big win by environmentalists, its motivations have more to do with economics than climate change. The Norwegian government, which gets 20 percent of its revenue from the petroleum sector, said Friday it wants to reduce its vulnerability to a permanent decline in the price of oil. The fund will eventually sell its investments in 150 oil exploration and production companies, which amounts to only 1.2 percent of its holdings. It’ll still invest in large, integrated oil companies like BP and Exxon Mobil.